Navigate to Homepage
Search
Main navigation
  

        
              Explore the Capitol Campus
                          Art
                            Buildings & Grounds
                            Capitol Hill Facts
                            Visitor Resources
                            Our Blog
                            What We Do
                          Areas of Expertise
                            Programs & Ceremonies
                            Projects
                            Publications
                            Strategic Objectives
                            About Us
                          Who We Are
                            History of the AOC
                            News & Notices
                            Organizational Structure
                            Partnerships & Recognition
                            Work With UsSearch Breadcrumb
    HomeWhat We DoAreas of Expertise
Masonry
        
                  Areas of Expertise
  

        
              Areas of Expertise
                                        Architecture
                                                Electrical
                                                Engineering
                                                Gardening
                                                Historic Preservation
                                                Masonry
                                                Mechanics
                                                Metal Work
                                                Painting and Plaster
                                                Plumbing
                                                Visitor Services
                                                WoodcraftingThe Architect of the Capitol (AOC) is responsible for the preservation and maintenance of the stone exterior of the U.S. Capitol as well as the exteriors of all of the other buildings on Capitol Hill.

As the buildings have aged, the challenge of caring for their ornate stone facades has only increased. The hands-on work caring for the stone found across Capitol Hill falls to AOC masons. These masons perform decorative brick, granite, marble and stone work including repairing stone and brick joints by cutting, raking, cleaning, and repointing with mortar and caulking compound. They also take care to mix color tone mortar to match the aging condition of work.

Meet the Stone MasonsIn addition, they re-construct falling or damaged marble cornices, cutting and replacing metal hangers, remounting, leveling and pointing up joints. They remove, repair and re-set marble moldings around doorways and are responsible for demolition and replacement of marble panels requiring metal hangers and plastic adhesive to re-set, in addition to finding durable matching stone.

"Each of the buildings on Capitol Hill was carefully designed and built, and we need to make sure we preserve and maintain what others created for future generations"

- Mary Oehrlein, AOC historic preservation officer

On the Job

Entrusted with the care of the buildings and the safety of all occupants and visitors, the AOC has proactively worked to identify fissures and defects in the stone by conducting stone surveys and removing any stones that appear weak.

One of the challenges of caring for stone is keeping up with its maintenance. Various techniques are used to preserve stone, such as repointing, a procedure that involves removing the deteriorating mortar surrounding the stone piece and replacing it with new mortar.

The crew that makes up the AOC's Construction Division Stone Mason Shop is a roving group, working on projects throughout Capitol Hill, going wherever the need is greatest.

One of the many projects they have tackled is the preservation of the low Olmsted boundary walls that ring much of Capitol Square. Completed in the 1870s by famed Capitol landscape architect Frederick Law Olmsted, the 5,500 linear feet walls made of granite and gneiss stone were in desperate need of repair. For a number of years, teams of stonemasons have worked to cut out the old mortar, reset the pieces and repoint the joints with new mortar.

"It's a lot of work to make sure all of the joints line up," says Russell Jones, a stonemason at the AOC for the past 21 years. Aside from hard work, the project also required ingenuity and creative solutions. To duplicate the historic look of beading in the mortar, Jones created a custom-made tool to ensure all of the mortar appears uniform.

The complex nature of their work requires that the stonemasons seek assistance from other AOC shops. If they need a specialized piece of equipment or labor assistance, the shops are always willing to help, making the stonemasons' projects true team efforts.
          
    
      Recent Stories
Related Articles
            
          Projects

  Olmsted Lanterns Restoration

The large bronze and glass lanterns are mounted on stately sandstone piers with intricately carved sandstone caps.
    Behind the Scenes

  Before and After: Hearing Room Renovation for the Senate Committee on Commerce, Science and Transportation

The Senate Office Buildings jurisdiction recently completed a project to restore the hearing room for the U.S. Senate Committee on Commerce, Science and Transportation (SR-253) in the Russell Senate Office Building.
    Behind the Scenes

  Behind the Scenes: Senate Office Buildings Masonry Branch

Some Architect of the Capitol employees are highly visible, while others work behind the scenes to preserve the awe-inspiring facilities on Capitol Hill. Go behind the scenes to learn more about the work of the Senate Office Buildings Masonry Branch beginning at 4 a.m. each morning.
    Behind the Scenes

  Cool Tools: Squaring Off With History

Many of the tools we use around the Capitol campus are unique, historic and essential to our mission — in other words, they are cool tools!

Areas of Expertise
Discover More
    
    Previous Image
          Next Image
        A person at a desk reviews room layout plans.

  Architecture
    AOC employee fixing lamp

  Electrical
    Engineer working on device

  Engineering
    Gardener holding flowers in greenhouse

  Gardening
    Pieces of stone sculpture.

  Historic Preservation
    Mason repairing molding on wall

  Masonry
    Senate Subway Branch Safety

  Mechanics
    Metal worker working on sheetmetal

  Metal Work
    AOC employee painting wall

  Painting and Plaster
    AOC plumber holding pipes

  Plumbing
    A visitor guide shows a tour group through the U.S. Capitol Rotunda.

  Visitor Services
    Three woodcrafters sketching a new design

  Woodcrafting

      We love our jobs. Do you? Come work with us.
        View Job Listings Serve. Preserve. Inspire.

              Contact Us
                            Accountability
                            Hill Staff Resources
                            AOC Staff Resources
Utility
  

        
              Privacy Policy
                            Image Terms of Use
                            Inspector General
                            U.S. Botanic Garden
                            U.S. Capitol Visitor CenterFacebook
	Twitter
	Flickr
	YouTube
	Instagram
	Subscribe